"Not all plant-based patterns of eating are healthy,” warns CVD study author

19 March 2020 - NutritionInsight

It concluded that the health benefits of plant-based dietary patterns are not a given and differences may exist between men and women. This research sheds light on CVD risk reduction measures at a time when both the plant-based diet’s popularity and CVD health concerns continue to rise. 

“Plant-based diets have been associated with a lower risk of non-communicable chronic diseases. CVD, the leading cause of morbidity and mortality, is at the top of the rank. It was surprising that our investigation found that not all plant-based patterns of eating are healthy,” the study’s lead author Dr. Demosthenes Panagiotakos, Professor of Biostatistics, Research Methods and Epidemiology at Harokopio University of Athens, tells NutritionInsight.

The higher the adherence to plant-based dietary patterns, the lower the risk for cardiac health was, found the study, which involved 2,000 Greek participants. Only people following a healthful plant-based diet had a significant reduction in cardiovascular risk compared to those who ate more animal-based products.

Here, plant-based diets weredefined as consuming few animal-based foods daily, as opposed to vegetarian diets eliminating animal-based meats and vegans abstaining from all animal products. 

“These findings highlight that even a small reduction in the daily consumption of animal-based products accompanied by an increase in healthy plant-based foods may contribute to better cardiovascular health,” says Dr. Panagiotakos. Healthful foods included fruits, vegetables, whole grains, nuts, legumes, oils and tea or coffee, while its unhealthy counterpart consisted of juices, sweetened beverages, refined grains, potatoes and sweets. 

The researchers tracked eating behavior and heart disease development over a 10-year period, beginning in 2002. Participants were asked to complete a detailed food frequency survey at the time of enrollment, after five years and after ten years.

In the early 2000s, there were not as many plant-based meat and dairy alternatives compared with today. “Unfortunately, such data was not that available in 2002 when the baseline dietary assessment was performed. Nevertheless, we do have reasons to believe that the inclusion of such products would not alter our final outcomes. Further studies are needed,” Dr. Panagiotakos explains. 

CVD assessment across genders

Differences in eating patterns – and associated cardiovascular risk reduction – were also observed between women and men. Overall, men eating fewer animal-based foods were 25 percent less likely to develop heart disease compared to men eating more animal-based foods. The same overall trend was observed in the women’s test group, but the relationship was not so pronounced, with an overall risk reduction of about 11 percent among women eating the fewest animal-based foods.

“It was interesting that the findings generated here were more evident in women. To this issue, women have a higher adherence to dietary patterns close to the plant-based concept with low consumption of animal products. However, it seems that this does not guarantee health food choices and, in turn, better health status.”

Moreover, men ate about three times per day while women tended to snack more, eating four to five times daily.  At the same time, women showed a more dramatic increase in heart disease risk when eating an unhealthful plant-based diet and a more dramatic reduction in risk when eating a healthful plant-based diet compared to men who fell into the same two categories. “This suggests that snacking on healthful foods can be beneficial, while snacking on unhealthful foods can bring higher risks,” Panagiotakos outlines.

Future prevention

This study’s findings have recently been mirrored by health lobby group Action on Salt, discovering high levels of sodium and saturated fats in many plant-based and vegan meals. Indeed, plant-based meat analogs have been called out for their high sodium and saturated fat levels, known CVD triggers, amid their praise for being an environmentally sustainable alternative to animal-based products. Especially in this nascent sector, consumers should be aware that plant-based meals often contain far more salt than non-plant-based options.

“Meatless Mondays” and “Veganuary” are effective means of reducing daily consumption of animal-based products, Dr. Panagiotaskos says. “Nevertheless, the plant-based patterns discussed here are not equivalent to vegetarian diets, that is, without animal-based protein,” he stresses.

“The dietary pattern we revealed as healthy here is more or less close to the traditional Mediterranean dietary pattern. Hence, a diet with a variety of foods, daily consumption of fruits, vegetables, whole-wheat grains and a moderate consumption of meat accompanied by low consumption of red meat as well as occasional consumption of sweets and beverages is what we can safely recommend,” he further states. 

Considering the recent tendency to adhere to sustainable diets, Dr. Panagiotaskos assesses the role of vegetarian, vegan and Mediterranean-style diets on the vascular system as “of high importance” to establish more specific recommendations on the topic of plant-based diets in the future.